Dichroic guest-host polarizer comprising an oriented polymer film

• US 7,763,330 B2
• Filed: 11/02/2004
• Issued: 07/27/2010
• Est. Priority Date: 11/06/2003
• Status: Active Grant

• Current Assignee: Sumitomo Chemical Company Limited
• Original Assignee: Sumitomo Chemical Company Limited
• Inventors: Lub, Johan, Peeters, Emiel, Broer, Dirk Jan
• Primary Examiner(s): HON, SOW FUN
• Application Number:
  US10/578,062
• Publication Number:
  US 20070024970A1
• Time in Patent Office: 2,093 Days
• Field of Search: 428/1.31, 349/97, 252/299.1, 359/491
• US Class Current: 428/1.31
• CPC Class Codes: C09K 19/3852 Poly(meth)acrylate derivatives
• CPC Class Codes: C09K 19/60 Pleochroic dyes
• CPC Class Codes: C09K 19/606 Perylene dyes
• CPC Class Codes: C09K 2219/03 in the form of films, e.g. films after polymerisation of LC precursor
• CPC Class Codes: C09K 2323/031 Polarizer or dye
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/13725 based on guest-host interaction G02F1/13762, G02F1/13737, take precedence

Abstract

A dichroic guest-host polarizer comprises an oriented polymerized liquid crystal host and aligned therewith a dichroic guest. The dichroic ratio of the polarizer is about 15 or more. The polarizer may have a small thickness, be manufactured using a wet deposition method, optionally in accordance with a desired pattern, and be provided on the inside of a liquid crystal cell. Polymerizable liquid crystals having a highly ordered mesophase which may be suitable used to obtain highly oriented polymer films such as polarizer films are disclosed.

Claims

1. A guest-host polarizer comprising an oriented polymer film including an oriented polymerized liquid crystal host and a dichroic light-absorbing guest dispersed and oriented in the host, the oriented polymer film having a dichroic ratio of about 15 or more;

wherein the orientation of the oriented polymer film is or corresponds to the orientation of a smectic phase S_x wherein the smectic phase S_x is not smectic A phase or smectic C phase, and wherein the oriented polymerized liquid crystal host is obtained by polymerizing an oriented polymerizable liquid crystal.

2. A guest-host polarizer as claimed in claim 1, wherein the oriented polymer film has a film thickness of about 10 μ

m or less.

3. A guest-host polarizer as claimed in claim 1, wherein the dichroic light-absorbing guest is a blue absorbing dichroic colorant and the polarizer further comprises a thin film obtained from a perylene-based, naphthalene-based or anthraquinone-based lyotropic liquid crystal or combination thereof.

4. A liquid crystal cell comprising a substrate, a liquid crystal layer and a guest-host polarizer as claimed in claim 1.

5. The liquid crystal cell of claim 4 wherein the guest-host polarizer is arranged between the liquid crystal layer and the substrate.

6. A liquid crystal cell as claimed in claim 5 wherein at least one of a compensation layer, a retarder layer, a color filter layer and a viewing angle layer or other optical layer is arranged between the substrate and the liquid crystal layer.

7. A method of manufacturing a guest-host polarizer comprising an oriented polymer film including an oriented polymerized liquid crystal host and a dichroic light-absorbing guest dispersed and oriented in the host, the oriented polymer film having a dichroic ratio of about 15 or more, the method comprising:

providing a thin film of a polymerizable liquid crystal host and, dispersed therein, a dichroic light-absorbing guest;

orienting the polymerizable liquid crystal host and the dichroic light-absorbing guest to obtain an oriented thin film of oriented polymerizable liquid crystal host and a dichroic light-absorbing guest dispersed and oriented in the host, the oriented thin film having a dichroic ratio of about 15 or more;

polymerizing the polymerizable liquid crystal host in the oriented state to obtain an oriented polymer film including an oriented polymerized liquid crystal host and a dichroic light-absorbing guest dispersed and oriented in the host, the oriented polymer film having a dichroic ratio of about 15 or more, and the orientation of the oriented polymer film is or corresponds to the orientation of a smectic phase S_x wherein the smectic phase S_x is not smectic A phase or smectic C phase.